黑莓 5.0 中的 Json 解析

Question

我正在黑莓 5.0 版中开发应用程序，并且我已经导入了 5.0 版中需要 json 的所有库。

我从这个 url 下载了库 http://supportforums.blackberry.com/t5/Java-Development/JSON-library/td-p/573687

即使我没有得到回应，我在这段代码中遗漏了什么请帮助我。

下面是我的 json 解析代码。

 package mypackage;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;

import javax.microedition.io.Connector;
import javax.microedition.io.HttpConnection;

import JSON_ME_Library.src.org.json.me.JSONArray;
import JSON_ME_Library.src.org.json.me.JSONException;
import JSON_ME_Library.src.org.json.me.JSONObject;

import net.rim.device.api.ui.UiApplication;
import net.rim.device.api.ui.component.ButtonField;
import net.rim.device.api.ui.component.Dialog;
import net.rim.device.api.ui.component.LabelField;
import net.rim.device.api.ui.container.MainScreen;


public final class MyScreen extends MainScreen
{

    String url="http://www.appymail.com/iphone-messenger/456842/";

    public MyScreen()
    {                
        setTitle("Json Parsing Sample");

         String aa=jsonresponse(url);

        if(aa.equalsIgnoreCase(""))
        {
            add(new LabelField("NO res"));
        }
        else
        {
            parseJSONResponceInBB(aa);

        }


    }



    void parseJSONResponceInBB(String jsonInStrFormat)
    {  


        try {  
            JSONObject json = new JSONObject(jsonInStrFormat);  
            JSONArray jArray= json.getJSONArray("messages");  

            //JSONArray arr=jArray.getJSONArray(0);

            for(int i=0;i<jArray.length();i++)
            {  
                JSONObject j = jArray.getJSONObject(i);  
                String from = j.getString("id");         
                add(new LabelField("id=="+from));

                String to =j.getString("title");
                add(new LabelField("title=="+to));           

                String message=j.getString("body");                
                add(new LabelField("Body=="+message));

            }  
        } catch (JSONException e) 
        {           
            e.printStackTrace();  
        }    



    }  

    public static String jsonresponse (String url) 
    { 
        String response = null; 
        HttpConnection httpConnection = null; 
        InputStream inStream = null; 
        int code; 
        StringBuffer stringBuffer = new StringBuffer();

        try { 

            httpConnection = (HttpConnection) Connector.open(url, Connector.READ); 
            httpConnection.setRequestMethod(HttpConnection.GET); 

            code = httpConnection.getResponseCode(); 

            if(code == HttpConnection.HTTP_OK) 
            { 
                inStream=httpConnection.openInputStream(); 
                int c; 


                while((c=inStream.read())!=-1) 
                { 
                  stringBuffer.append((char)c); 
                } 
                response=stringBuffer.toString(); 
                System.out.println("Response Getting from Server is ================" + response); 



            }
        else 
            { 
                UiApplication.getUiApplication().invokeLater(new Runnable() 
                { 

                    public void run()
                    {       
                        Dialog.inform("Connection error"); 
                    } 
                }); 
            } 


        } 
        catch (Exception e) 
        { 

            System.out.println("caught exception in jsonResponse method"+e.getMessage()); 

        } 
        finally
        {

        //      if (outputStream != null) 
        //      { 
        //          outputStream.close(); 
        //      }
                if (inStream != null) 
                { 
                    try {
                        inStream.close();
                    } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    } 
                }
                if (httpConnection != null ) 
                { 
                    try {
                        httpConnection.close();
                    } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    } 
                } 
        }

        return response; 
    }


}

Answer 1

您好，亲爱的，您需要为黑莓使用 url 扩展名

所以请尝试更改此行

  String aa=jsonresponse(url); 

作为

String aa=jsonresponse(url+";interface=wifi");

成功完成从 url 下载数据后，检查 String aa 是否有任何值？如果它得到数据然后跟随

如果它工作正常，请尝试此操作，然后通过以下链接进行操作

Guide for URL extensions

Answer 2

输入网址

     String url="Your url";
     String request=jsonresponse(url+";interface=wifi");
     String response = parseJSONResponceInBB(request);
     if(response .equalsIgnoreCase(""))
     {
        add(new LabelField("NO res"));
     }
     else
     {
        add(new LabelField(response ));
     }